1. Field of the Invention
The invention relates to a side collision determination apparatus for a vehicle which determines whether a colliding object has collided with a side surface of a vehicle and a high voltage power supply shut-off apparatus which determines that a colliding object has collided with a side surface of an electric vehicle and thus shuts off power supply to a high voltage part of a high voltage power supply.
2. Description of the Related Art
Regarding a side collision of a vehicle, there is a related art which determines the side collision using acceleration sensors mounted to a side surface of the vehicle and deploys a safety apparatus such as an airbag.
In many cases, the acceleration sensors are mounted to B pillars that are columns supporting a roof of the vehicle and are positioned at centers of side surfaces. The related art suggest detecting a distance to the colliding object or provide other sensors such as a deformation sensor, a pressure sensor and the like (for example, Patent Documents 1 to 3).
An electric vehicle is provided with a high voltage power supply for driving a motor. When the vehicle body is damaged due to the collision, a part relating to the high voltage, a safety belt and the like may be damaged. In order to prevent an occupant or helper from contacting the damaged part or harness or to prevent another part from being damaged, the high voltage power supply is shut off when the collision is detected (for example, Patent Document 4). The shut-off operation of the high voltage power supply may be performed on the basis of information of the acceleration sensors for the safety apparatus such as an airbag and the like.    [Patent Document 1] JP-A-2008-137491    [Patent Document 2] JP-A-2009-90816    [Patent Document 3] JP-A-2009-101837    [Patent Document 4] JP-A-2007-118797
When a collision, which is a trigger for shutting off the high voltage, is a side collision, it is necessary to detect all of collisions from the front to the most rearward of the side surface of the vehicle. Regarding the side collisions of the front and the center of the side surface, it is considered to detect the collisions with the acceleration sensors and the like for the airbag, which are mounted to the B pillars, and to thus shut off the high voltage.
However, when an object collides with a part of the vehicle adjacent to the B pillar, a part of the vehicle body neighboring to the acceleration sensor is damaged, so that the acceleration sensor or harness may be damaged. As a result, a direction of a sensitive axis of the sensor is changed, so that it is not possible to accurately detect the acceleration occurring in the vehicle body.
In addition, when the side collision occurs at the most rearward part of the side surface, the vehicle body is rotated since a center of the vehicle is apart from the collision position. As a result, it may be difficult to detect the collision using the acceleration sensors mounted to the B pillars and the like. To solve the problem, it is necessary to mount a separate acceleration sensor at the rear part of the side surface. However, a space for mounting the sensor should be secured and the cost is increased.